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161.
针对陆军部队维修作业仿真评估需求,提出了一套仿真模型设计方案。分析了部队维修作业能力仿真评估原理,进而明确了评估模型需求;给出了维修任务生成、维修保障系统建模方案;结合备件调度和保障设备使用过程,设计了维修保障资源模型。为陆军部队装备维修作业能力评估提供建模基础,用于支撑部队维修作业能力仿真评估系统的设计和应用案例研究。  相似文献   
162.
Aiming at on-line controlling of Direct Methanol Fuel Cell (DMFC) stack, an adaptive neural fuzzy inference technology is adopted in the modeling and control of DMFC temperature system. In the modeling process, an Adaptive Neural Fuzzy Inference System (ANFIS) identification model of DMFC stack temperature is developed based on the input-output sampled data, which can avoid the internal complexity of DMFC stack. In the controlling process, with the network model trained well as the reference model of the DMFC control system, a novel fuzzy genetic algorithm is used to regulate the parameters and fuzzy rules of a neural fuzzy controller. In the simulation, compared with the nonlinear Proportional Integral Derivative (PID) and traditional fuzzy algorithm, the improved neural fuzzy controller designed in this paper gets better performance, as demonstrated by the simulation results.  相似文献   
163.
国际重要检索系统与甘肃省科技期刊   总被引:1,自引:1,他引:0  
对国际重要检索系统进行了论述,并对甘肃省科技期刊被国际重要检索系统收录情况进行了统计与分析。  相似文献   
164.
We have reported that chymotrypsin B (CtrB) is not just a digestive enzyme but is also stored in lysosomes. Herein, we demonstrated a broad distribution of CtrB and explored the involvement of CtrB in apoptosis. Exposure of RH-35 cells to H2O2 or palmitate induced the redistribution of lysosomal CtrB into the cytoplasm as a result of lysosomal membrane permeabilization (LMP). Suppression of CtrB significantly blocked apoptosis, while overexpression of CtrB sensitized apoptosis markedly. CtrB could cleave Bid under neutral conditions. In RH-35 cells with Bid silenced, apoptosis induced by CtrB protein was attenuated, suggesting that CtrB mediates apoptosis of RH-35 cells mainly through processing Bid. Our data also suggest that LMP occurs earlier than mitochondrial outer membrane permeabilization; Bid activation initiated by caspase-8 might be reinforced by CtrB in consequence of LMP, which causes a positive feedback loop leading to the accumulation of tBid, and results in lysosome- and mitochondrion-dependent apoptosis.  相似文献   
165.
Lin Z  Bei JX  Shen M  Li Q  Liao Z  Zhang Y  Lv Q  Wei Q  Low HQ  Guo YM  Cao S  Yang M  Hu Z  Xu M  Wang X  Wei Y  Li L  Li C  Li T  Huang J  Pan Y  Jin O  Wu Y  Wu J  Guo Z  He P  Hu S  Wu H  Song H  Zhan F  Liu S  Gao G  Liu Z  Li Y  Xiao C  Li J  Ye Z  He W  Liu D  Shen L  Huang A  Wu H  Tao Y  Pan X  Yu B  Tai ES  Zeng YX  Ren EC  Shen Y  Liu J  Gu J 《Nature genetics》2012,44(1):73-77
To identify susceptibility loci for ankylosing spondylitis, we performed a two-stage genome-wide association study in Han Chinese. In the discovery stage, we analyzed 1,356,350 autosomal SNPs in 1,837 individuals with ankylosing spondylitis and 4,231 controls; in the validation stage, we analyzed 30 suggestive SNPs in an additional 2,100 affected individuals and 3,496 controls. We identified two new susceptibility loci between EDIL3 and HAPLN1 at 5q14.3 (rs4552569; P = 8.77 × 10(-10)) and within ANO6 at 12q12 (rs17095830; P = 1.63 × 10(-8)). We also confirmed previously reported associations in Europeans within the major histocompatibility complex (MHC) region (top SNP, rs13202464; P < 5 × 10(-324)) and at 2p15 (rs10865331; P = 1.98 × 10(-8)). We show that rs13202464 within the MHC region mainly represents the risk effect of HLA-B*27 variants (including HLA-B*2704, HLA-B*2705 and HLA-B*2715) in Chinese. The two newly discovered loci implicate genes related to bone formation and cartilage development, suggesting their potential involvement in the etiology of ankylosing spondylitis.  相似文献   
166.
Opisthorchis viverrini-related cholangiocarcinoma (CCA), a fatal bile duct cancer, is a major public health concern in areas endemic for this parasite. We report here whole-exome sequencing of eight O. viverrini-related tumors and matched normal tissue. We identified and validated 206 somatic mutations in 187 genes using Sanger sequencing and selected 15 genes for mutation prevalence screening in an additional 46 individuals with CCA (cases). In addition to the known cancer-related genes TP53 (mutated in 44.4% of cases), KRAS (16.7%) and SMAD4 (16.7%), we identified somatic mutations in 10 newly implicated genes in 14.8-3.7% of cases. These included inactivating mutations in MLL3 (in 14.8% of cases), ROBO2 (9.3%), RNF43 (9.3%) and PEG3 (5.6%), and activating mutations in the GNAS oncogene (9.3%). These genes have functions that can be broadly grouped into three biological classes: (i) deactivation of histone modifiers, (ii) activation of G protein signaling and (iii) loss of genome stability. This study provides insight into the mutational landscape contributing to O. viverrini-related CCA.  相似文献   
167.
为探究植物性杀虫剂鱼藤酮、藜芦碱对蚯蚓的影响选择赤子爱胜蚓(Eisenia foetida)为受试生物,通过急性毒性实验和抗氧化酶活性测定,揭示鱼藤酮、藜芦碱的毒性效应。结果显示,急性染毒试验鱼藤酮对蚯蚓24h、48h的半致死质量浓度分别为23.96mg/L、5.991mg/L,藜芦碱对蚯蚓24h、48h的半致死浓度分别为40.67mg/L、20.33 mg/L。说明藜芦碱、鱼藤酮对蚯蚓有致死效应,鱼藤酮的毒性强于藜芦碱;蚯蚓体重的增长受到了药物浓度的影响,有较明显的剂量效应关系,但随时间的延长对蚯蚓体重的抑制效应减弱;在药物胁迫下,SOD与POD活性变化随质量浓度增大呈现先上升后下降,蚯蚓体内SOD、POD响应不同,POD对药物响应更敏感。  相似文献   
168.
面向跟踪任务需求的主动传感器调度方法   总被引:1,自引:0,他引:1  
以多传感器多目标跟踪为背景,针对跟踪任务需求中辐射风险控制问题,提出一种面向跟踪任务需求的主动传感器调度方法。该方法首先结合不敏卡尔曼滤波,给出了仅考虑跟踪任务需求的传感器调度策略;然后建立基于部分可观马尔可夫决策过程的辐射模型,并采用隐马尔可夫模型滤波器动态更新传感器辐射;最后考虑跟踪任务需求和传感器约束,将辐射风险控制下传感器调度问题转化为非线性约束下寻优问题。仿真实验结果验证了所提方法有效性。  相似文献   
169.
Environmental problem is one of complicated social problems. According to the level of corporate environmental management, there are many influential factors, and their relations are also complicated. In this paper, we analyzed influential factors of corporate environmental management through consultation of experts. And based on the analysis, we applied interpretative structural modeling(ISM) to classify 13 influential factors into 3 levels. We hope it will be useful for the subsequent research and evaluation of corporate environmental management level.  相似文献   
170.
很多文章均指出雷达网系统具有航迹快速起始的性能,但是尚没有资料从理论上对此加以证明。通过对雷达网系统平均扫描周期的研究,从理论上证明了雷达网系统具有航迹快速起始的性能,这对于研究雷达网系统的反电子对抗性能和评估准则具有特别重要的意义。  相似文献   
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